1. Field of the Invention
The present invention relates to a tool for installing rivets on and a method for connecting tool components, and more particularly, to a quick disconnect assembly for a tool head.
2. Description of the Related Art
Many manufacturing processes employ fasteners or rivets to permanently join one workpiece to another. One common rivet includes a rivet sleeve or body, and a rivet stem which extends through the sleeve with an enlarged head at the end opposite a rivet head on the sleeve.
Typically, to fasten two or more workpieces together, the rivet is placed through a hole in the workpieces such that the underside of the rivet head is flush against the workpiece while the tail of the sleeve and the head on the stem extend beyond the workpiece. While holding the rivet sleeve in place, the rivet stem is pulled axially further into a central bore in the sleeve such that the rivet stem head deforms and expands the tail of the rivet body on the backside of the workpieces. As the tension in the stem increases, the stem eventually breaks at a predefined location such that the stem head and the stem shank remain with the sleeve while the remainder of the stem shank is pulled free and discarded. The rivet is then permanently locked in place by the rivet head on the frontside surface of the workpieces and the expanded rivet body on their backside surface, thereby permanently fastening the workpieces together.
To perform the rivet setting operation described above, specially designed rivet setting tools have been developed that employ pneumatic or hydraulic pressure to actuate the device and set the rivet. While complex mechanically, these pneumatic and hydraulic tools are often preferred because they are stronger, faster, and more consistent than their human-powered counterparts.
One drawback of these devices, however, is that during operation a rivet can get jammed in the head of the rivet setting tool. When this occurs, the rivet setting tool is disabled and cannot operate further until the offending rivet is extracted from the tool head and the rivet setting tool is reset. Because traditional tool heads are attached to the rivet setting tool via screw threads, removal of the tool head requires the operator to use a wrench to loosen the tool head and then unscrew the tool head from the rivet setting tool. Further, a collet within the tool head must be separated from a drawbar, that reciprocates in the tool, before access can be had to the fastener gripping jaws and the obstructing fastener. Attaching a new tool head to the rivet setting tool is accomplished by the reverse operation but properly positioning and holding the jaws and other internal components while attaching the collet to the drawbar, is difficult and time consuming.
While the tool head replacement is being performed, the rivet setting tool is non-operational. If the tool is in an automated production line, this tool shut down creates a bottleneck in the entire production line, resulting in lost time and money. Consequently, the users of pneumatic- and hydraulic-powered rivet setting tools have long been in need of an apparatus and method for quickly rectifying these rivet jams.